Brake drum



J. v. PUGH.

Dec. 16, 1930.

BRAKE DRUM Filed No'v. 22, v1926 l ever, presents Ydilii'culties.-

Patented Dec. 16,VV 1930 l i' nN 1'1|a;n'STAT-asv PATENT oFFlcE JOHNVERNON PUGH, oF covENTRY, .ENG-LAND, .AssIGNon "ro RUDGE-WHITWOBTH,

Y LIMITED, oFfcovEN'rnY, ENGLAND M vnaaiznnmnwr Application mea november22, 192s, serial No.

This invention relates to rotational devices including vehicle wheelsandthe parts associated therewith such as brake drums and l' the like. A

It is generally desirable that the tires of vehicle wheels'should notstand any farther awayr from the sideof the vehicle than can be-helpedand for this reason the room taken up by a brake ,drum is frequentlyreduced by locating the drum within an enlargement of the wheel hub.This,.however, greatly increases the cost of the hub and to some 'degreethe same effect results from enlarging the outer. hub part sullicientlyto accommodate the bolt ends orlanges by which-a brake drum is attachedto the inner hub part of a detachable wheel.l y

The attachment of brake drums and the like by means of a hollowA conicalregion pressed against a conical abutment has been proposed and for thispurpose a, thin diaphragm or likecentral part of the brake' drum orother element is desirable. The formation of lar e diameter, elements ofsui- 25 cient rigidity om thin material alone, how- The object of thepresent invention is to overcome the foregoing diiiiculties and toprovide improved forms of brake drums and ,30 like elements. o

The invention consists in abrake drum or like rotational device havingacentral diaphragm constructed of thin material in combination with, acircular or encircling part of more rigid construction which is fastenedv to the diaphragm by -aseries of attachment means distributedpreferably equidstantly around theaxis of rotation and which increasesthe stiffness of the structure. s, The invention further consists in arotational-device 'in accordance with the preceding paragraph, in whichvthe centralrthinv diaphra is provided with a hollow conical attac entregion. y i The invention further consists in a rotational' device inaccordance with either of thel preceding paragraphs in which a hollowcylindrical encircling part constituting a brake drum is fastened at oneedge to 'the lio attachment diaphragm and has connected to15o,o944,'and`in Great afnamy December 1, 1925.:

its other edge an annular ring of suicient radial width to stiien thestructure.

The-invention further consists in a device in accordance with any ofthepreceding paragraphs in which the' diaphragm or annular ring extendsradially beyond the encircling part to provide stiliening means in thenature of aflange or anges. Y

The invention further consists in a device in accordance with any of thepreceding paragraphs -in which a hollow cylindrical encircling part of abrake drum is stiffened by means of one, two or a plurality of circularviianges or ribs projecting therefrom for use as attachment means o rfor dissipating heat.

The invention further consists in a device in accordance with any of thepreceding paragraphs in combination with a wire spoke vehicle wheelhaving one row of spokes at each end of the hub which are both connectedto that edge of the rim which is remote from the vehicle.

The invention also consists in improvements in or relating to rotationaldevices such as brake drums for vehicle wheels as hereinafter described.Referring'nowto the accompanying drawmgszv A Figure 1 shows a brake ringor drum in accordance with the invention;

igure 2 shows asimilar-arrangement with somemodliieatlons5 I l y Flgure3 is a fragmental view showlng a brake ring of somewhat differentconstrue'- Figure 4 is another fragmental view of a modified form'of thebrake ring.

`Figure 5 shows another way offorming the central diaphragm or disc. f'

In carrying` the invention into eii'ect in one convenient form asillustratedvby way of example in Figure 1 or 2, a wheel having wirespokes is provided with a built-up brake drum adapted to liecloselyadjacent to the spokes on the 'inner side ofthe wheel and projectingtowards the vehicle a distance corresponding to or not very greatlyexceeding the free or unspoked portion of the tirev rim., The brake drumis built up from a cen tral vdlaphragmr a formed of2 thin material, say

' 4:. towar-ds the wheel rim by y of 1/20 of an inch or more inthickness. The

diaphrgam is preferably formed with a central hollow conical region band the gripping ofthis region between the two hub parts and attachmentand driving means may be of* any suitable thin metal construction.

The flat part a1 of the diaphragm a may be disposed so as to just clearthe inner edge of the outer hub part which may be as shown slightlyflared to form a cavity and flanged From the larger/diameter end` of ahollow` conical region b the diaphragm extends as a flat dise al toabout the middle of its width and is then set out or carried towards thewheel spokes by' means of a frusto-conical region c and' then againtakes the form of a flat disc a2 or annular zone extending to the outeredge of the diaphragm. Alternatively the diaphragm may be formed as avery blunt cone as shown in Figure 5 extending from the end of thehollow conical gripping region-up to the attachment to the cylindricalpart of the brake drum.

The brake drum may be formed as a hollow cylindrical casting d havingstiffening or heat radiating ribs e upon its outer surface and anout-turned flange f provided at the edge of the brake ring remote fromthe vehicle for attachment to the diaphragm a and the diaphragm may beprovided with a turned-up edge a4 in order to stifl'en the structure.Alternatively the diaphragm may be extended from this edge as shown inFigure any desired amount for the same purpose.'

The edge of the brake ring d adjacent -to the vehicle may also beprovided with a stifl'ening flange h1 and be attached thereto by theflange l1, as shown in Figure 4 and with such -a construction-there mayalso be employed a plain cylindrical brake band d? such as may be formedfrom steel or thelike with outwardly-turned flanges f and h at each endfor attachment to the diaphragm and to a stif'fening ring h1.

Taking the rubbing surface of a suitable brake ring as being 400 mm. indiameter, the outside diameter, say of flanges, may be considerablylarger, say up to 500 or 60() mm., and this construction may be adoptedboth in the diaphragm and in 'a-stillening ring at the inside edge ofthebrake ring. In some instances dependingiupon the type of brake gearemployed, the internal diameter of an insidestiiening ring would be thesame size as the rubbing surface of the brake ring but where possiblethe inside"diameter of a stillening ring could be made considerablysmaller down to 300 mm. and in suchcases the quantity ofmaterial .usedinthe flange would be more valuable where it extends inwardly than whereit extends outwardly.

As shown in Figure 3 a brake ring d1 is formed with a flange l inturnedfrom its inner surfaceat the end remote from the ve-` hicle forattachment to the-outer edge a3 of the diaphragm by means of rivets jl,a cast cylindrical aluminium .drum being lined with steel as at g orother suitable material when desired.

A brake drum' ring may be constructed as a comparatively shallowmulti-ribbed band and can be made of steel rolled out after the manneradopted with hea-Vy wheel 'tires or may be made of a strip bent aroundand welded,'the strip being either of rectangular section and machinedafter rolling and welding or rolled to final section as in Figure l orFigure 4 and then welded, or a ring can be made of malleable casting orin some cases of ordinary cast iron, in which latter case encircling andtensioned wires or the like may be used as reinforcements in the groovesbetween ribs such as e. y A

Rims as hereinbefore described may be conveniently fastened to thediaphragm by means of a number of screws 7' and between the diaphragmand the rim, washers c either of asbestos or some other deadeningmaterial may be inserted to obviate vibration or noise. ln some casessteel or other metal washers may be satisfactorily 'employed and willprovide a gap between the rim and the diaphragm so as to get rid of anyoil leaking on to these regions. l

Brake drums as hereinbefore described may be employed with any ordinarywire spoke wheels having beaded edge, well4 base or other types of rims.They may also if desired be employed with wheels of any other suitableconstruction.

.It is to be understood that the constructions hereinbefore describedare given by Way of example only and that modifications and additionsmay be introduced without'in anyway departing from the spirit of this1nvention.

I claim: l

1. A vehicle wheel braking device having in combinationl a thin platemetal disc upset centrally from a llat plate. to afford .increasedrigidity and a vehicle wheel brake ring of not less than double thethickness of the material of said disc fastened thereto by a series oftachment means distributed around the axls of rotation.

2. A device in accordance with claim l. 1u which the central thin discis provided with a central hollow conical attachment region.

3. A device in accordance with claim 1 1n which the disc is providedwith an outer annulns whiclris set up by a step and hes 1n a plane ofrotation further'from the vehicle/ 4. A device in accordance with claim1 in which a ring of the material of the thin disc part extends beyondthe means for attaching said disc to the brake drum, said ring. beingunattached to any other part and acting solely as stiffening means. l

5. A vehicle wheel brake drum comprising in combination a sheetmetal-disc, a centrally apertured hollow conical `ragion projectingoutwards therefrom, an outwardly set-up region occupying the outer partof said disc, an inwardly turned rim around the periphery of said set-upregion, a flanged brake ring having an interior contact area and nestedwithin said rim, and a series of ttachment means fastening said ring tosaid isc.

6. A vehicle wheel brake drum comprising in combination -a sheet metaldisc, a centrally apertured hollow conical region projecting outwardstherefrom, an outwardly set-up region occupying the outer part ofv saiddisc, a flanged brake lring with an interior contact area, and a seriesof attachment means fastening said ring to said disc some distancewithin the outer periphery thereof.

7. A vehiclewheel brake drum comprising in combination a sheetimetaldisc, a centrally apertured hollow conical region projecting. outwardstherefrom, an outwardly set-up region occupying the outer art of saiddisc, an externally flanged and ribbed brake ring, an interior surface.rovided within said ring for Contact with riction means, anda series ofattachment means fastening a flange of said brake ring to said disc.

8. A vehicle wheel brake drum comprising in combination a sheet metaldisc, a centrally an interior rubbing surface nested within an interiorrubbing surface, a series of at.

tachment means fastening said ring to saidl disc, and washers formed ofdeadening ma terial inserted between said disc and ring .at each of saidattachment means.

In testimonywhereof I have signed my name to this specification.

JOHN VERNON PUGI-I.

apertured hollow conical region projecting outwards therefrom, anoutwardly set-up region occupying the outer part of said disc, aninwardly turned rim around the eriphery of said set-up region, a brakering fianged eX- ternally at each end with an interior. surface forcontact nested within said rim, and a` series of attachment meansfastening one flange of said ring to said disc.

9. A vehicle wheel brake drum comprising in combination a sheet metaldisc, a centrally apertured outwardly projecting hollow conical memberattached concentrically thereto, an outwardly set-up region occupyingthe outer part of saiddisc, a brake ring with eX- ternal flanges atYeach end and havingv an interior surface f or contact, and -a series ofattachment means fastening said ring to said disc.

10. A vehicle wheel brake. drum compris-' ing in combination a sheetmetal disc, a centrally apertured hollow conical element attachedthereto and projecting centrally outwards therefrom, an outwardly set-upregion occupying the outer part of said disc, an' inwardly turned rimaround the periphery of said set-up region, a flanged brake ring withsaid rim, and a series of attachment means

